Working on Knock Sensor, oh boy
05-24-2002, 05:11 PM
#1
Working on Knock Sensor, oh boy
So I'm in the middle of it right now. Its just like other members have posted, the terminals are all corroded. There is a technical serive bulliten for this problem. Unfortuanatley its a lot of work to get down to it and do a good job. I'm hoping this has something to do with poor fuel economy, I'll be posting results in performance as well. The TSB says that the timming is retarded dramatically, something like 8-10 degrees during WOT (so its affecting 1/4 mile times as well). In the next comming week I'll be getting dyno work done (courtesy of Unorthodox) and then results for the new UDP from them will be posted. The max was running excellent before this project, so I'm excited to see what else I've been missing
Just to mention if any of you are crazy enough to do this job (its not that bad really), but you should definitley open both cylinder coolant plugs. b/c the cooland ****ed all over the middle of the engine while I was in the middle of it. And also to mention to all of you guys that wash your motor, DONT b/c There is a nice reservoir that forms in the middle of the engine under the intake manifold (like 3 inches deep) and it does not drain out. The pond will submerge the knock sensor making the teminals worse. I plan to seal the knock sensor with RTV silicone to prevent moisture from getting to the terminals in the future.
Just to mention if any of you are crazy enough to do this job (its not that bad really), but you should definitley open both cylinder coolant plugs. b/c the cooland ****ed all over the middle of the engine while I was in the middle of it. And also to mention to all of you guys that wash your motor, DONT b/c There is a nice reservoir that forms in the middle of the engine under the intake manifold (like 3 inches deep) and it does not drain out. The pond will submerge the knock sensor making the teminals worse. I plan to seal the knock sensor with RTV silicone to prevent moisture from getting to the terminals in the future.
05-25-2002, 07:05 AM
#2
Junior Member
Join Date: May 2002
Posts: 23
Re: Working on Knock Sensor, oh boy
Hi,
That what happened to me after washing my engine (92 SE auto), i've started experiencing loss of power as well as engine shut downs during any speed and also causing tranny to go beserk sometimes. Can it be due to the knock sensor terminals corroded?
I've tried everything pls post some more info of how to get down to it. Thanks.
That what happened to me after washing my engine (92 SE auto), i've started experiencing loss of power as well as engine shut downs during any speed and also causing tranny to go beserk sometimes. Can it be due to the knock sensor terminals corroded?
I've tried everything pls post some more info of how to get down to it. Thanks.
05-25-2002, 09:55 AM
#3
I dont think the KS is whats causing your trouble. Its probably another connector that needs to be cleaned. You wont feel any poor drivability from the KS terminals being corroded. But there is a big performance loss due to the timming being retarded by the ecu.
Some general info:
resistance: before ~~(4) Meg ohm
After cleaning ~~(.5) Meg ohm (the same as another member who had tested a new KS)
So the resistance of the KS can be tested to see if the terminals are badly corroded or not. For those who do not know where to accesible connector is I'll try to position it for you. It's on the right side of the motor (side with battery), a couple inches away from the transistor pack or camshaft sensor towards the cabin. So the connector has two terminals but only one is actually being used (they must have had some reason for this, may have to do with the operation of the pezoelectric element), so you would have to check resistance between one of those terminals and the neg. on the batt. (or another ground spot). remember that one terminal does not do anything, so you would have to check both to find the right one.
The terminals on mine were so corroded that when I pulled the connector off the KS, that there was a small cloud of oxide dust, and the damn connector was sticking like glue. I'm still not dont with the job b/c I have to let all the silicon cure fully. I'm really looking foward to doing a test drive, I want to see If I can melt some tire rubber
with my auto.
Some general info:
resistance: before ~~(4) Meg ohm
After cleaning ~~(.5) Meg ohm (the same as another member who had tested a new KS)
So the resistance of the KS can be tested to see if the terminals are badly corroded or not. For those who do not know where to accesible connector is I'll try to position it for you. It's on the right side of the motor (side with battery), a couple inches away from the transistor pack or camshaft sensor towards the cabin. So the connector has two terminals but only one is actually being used (they must have had some reason for this, may have to do with the operation of the pezoelectric element), so you would have to check resistance between one of those terminals and the neg. on the batt. (or another ground spot). remember that one terminal does not do anything, so you would have to check both to find the right one.
The terminals on mine were so corroded that when I pulled the connector off the KS, that there was a small cloud of oxide dust, and the damn connector was sticking like glue. I'm still not dont with the job b/c I have to let all the silicon cure fully. I'm really looking foward to doing a test drive, I want to see If I can melt some tire rubber
with my auto.
05-26-2002, 12:18 PM
#4
So no melting of rubber (damnn that LSD). But there is a noticable increase in low end. I hope this is going to solve my poor fuel economy, just about everything else has been replaced/tuned-up and the car is running really good.
When I was installing the throttle cables I tightened down the wrong nut and it pulled the TB, so when I started the engine up it was racing, didnt take long to figure it out. But no real problems were incountered with the job.
Next stop Unorthodox.....
When I was installing the throttle cables I tightened down the wrong nut and it pulled the TB, so when I started the engine up it was racing, didnt take long to figure it out. But no real problems were incountered with the job.
Next stop Unorthodox.....
05-26-2002, 09:48 PM
#5
So now after driving it another day I have found that the increase in low end is pretty significant. It now pulls with more low end than it is with high end. Before it was the opposite, go figure.
05-26-2002, 10:13 PM
#6
Senior Member
Join Date: Jan 2001
Posts: 2,105
Originally posted by eric93SE
So now after driving it another day I have found that the increase in low end is pretty significant. It now pulls with more low end than it is with high end. Before it was the opposite, go figure.
So now after driving it another day I have found that the increase in low end is pretty significant. It now pulls with more low end than it is with high end. Before it was the opposite, go figure.
new coils?
new injectors?
also, anything i should know before tackling this job (replacement parts, tools..)
05-27-2002, 10:04 AM
#7
Yup functioning VTC's
Yup just recently removed, cleaned, and installed all new seals on the injectors.
Yup all ignitions coils have been replaced within one year.
Here is a link for the injector job I did. I do reccomend doing this if you wanna do the knock sensor at the same time, I wish I had!
http://forums.maxima.org/showthread....ht=pintle+caps
I highly reccomend the kit beck arnley makes, its complete, and a resonable price!
Just one other thing I'd like to mention. The intake manifold gasket is VERY expensive. Dealer wants like $90/each. Aftermarket prices vary. I did decide to reuse the originals (they are thick steel, with rubber inserts) and I used a high temperature permatex gasket maker around all the sealing surfaces.
Yup just recently removed, cleaned, and installed all new seals on the injectors.
Yup all ignitions coils have been replaced within one year.
Here is a link for the injector job I did. I do reccomend doing this if you wanna do the knock sensor at the same time, I wish I had!
http://forums.maxima.org/showthread....ht=pintle+caps
I highly reccomend the kit beck arnley makes, its complete, and a resonable price!
Just one other thing I'd like to mention. The intake manifold gasket is VERY expensive. Dealer wants like $90/each. Aftermarket prices vary. I did decide to reuse the originals (they are thick steel, with rubber inserts) and I used a high temperature permatex gasket maker around all the sealing surfaces.
05-27-2002, 11:45 AM
#8
Senior Member
Join Date: Oct 2001
Posts: 353
Originally posted by eric93SE
Yup functioning VTC's
Yup just recently removed, cleaned, and installed all new seals on the injectors.
Yup all ignitions coils have been replaced within one year.
Here is a link for the injector job I did. I do reccomend doing this if you wanna do the knock sensor at the same time, I wish I had!
http://forums.maxima.org/showthread....ht=pintle+caps
I highly reccomend the kit beck arnley makes, its complete, and a resonable price!
Just one other thing I'd like to mention. The intake manifold gasket is VERY expensive. Dealer wants like $90/each. Aftermarket prices vary. I did decide to reuse the originals (they are thick steel, with rubber inserts) and I used a high temperature permatex gasket maker around all the sealing surfaces.
Yup functioning VTC's
Yup just recently removed, cleaned, and installed all new seals on the injectors.
Yup all ignitions coils have been replaced within one year.
Here is a link for the injector job I did. I do reccomend doing this if you wanna do the knock sensor at the same time, I wish I had!
http://forums.maxima.org/showthread....ht=pintle+caps
I highly reccomend the kit beck arnley makes, its complete, and a resonable price!
Just one other thing I'd like to mention. The intake manifold gasket is VERY expensive. Dealer wants like $90/each. Aftermarket prices vary. I did decide to reuse the originals (they are thick steel, with rubber inserts) and I used a high temperature permatex gasket maker around all the sealing surfaces.
Yeah i realise there is a search engine, but I guess it just makes life easier. Especially for me, a person who don't know crap but would like to read about these things.
P.S.
Why does the 350Z and the G35 coupe look so much alike? Arn't they going after the same market? with about the same price, with the "same" (used loosly) skyline inheritance?
05-27-2002, 08:45 PM
#9
Originally posted by Aphrodisiac
you know this might be a stupid request, but I dunno. I'd like to see all these kinds of posts dedicated in a certain section so people can refer to them.
Yeah i realise there is a search engine, but I guess it just makes life easier. Especially for me, a person who don't know crap but would like to read about these things.
P.S.
Why does the 350Z and the G35 coupe look so much alike? Arn't they going after the same market? with about the same price, with the "same" (used loosly) skyline inheritance?
you know this might be a stupid request, but I dunno. I'd like to see all these kinds of posts dedicated in a certain section so people can refer to them.
Yeah i realise there is a search engine, but I guess it just makes life easier. Especially for me, a person who don't know crap but would like to read about these things.
P.S.
Why does the 350Z and the G35 coupe look so much alike? Arn't they going after the same market? with about the same price, with the "same" (used loosly) skyline inheritance?
). I think the competition (ASP) claims there pulley makes 8hp, so I'm aiming for 10-12hp on my motor (mostly stock). I'd like to get to the track and see what kind of 1/4 mile times I can achieve with the new pulley, most say somewhere between 3-4 tenths or something. I dont know If I'll have time to get to the track before or not.And the 350Z (nissan), and the G35 (infinity), Since they are really the same make there will be a lot of common similarities. But unfortunatley stying should not be one of them.
06-01-2002, 09:28 AM
#11
Congrats, Eric.. You made the first new sticky.
I'll at least stick it at the top of the page for a while, and when I get time I'll archive them all into one post and then "unstick" them so they don't sit at the top of the screen and take up the first two pages like the other forums.
But anyway, good work. I'll take a look at mine this afternoon. my car's really been sucking ***** on the low end. once I hit about 3000 rpm, you can hear the tone of the engine change and the thing just PULLS. and it's not VTC of the power valve. something else, and it's been getting worse as the weather warms up. sounds like a knock sensor/octane problem to me.
I'll at least stick it at the top of the page for a while, and when I get time I'll archive them all into one post and then "unstick" them so they don't sit at the top of the screen and take up the first two pages like the other forums.
But anyway, good work. I'll take a look at mine this afternoon. my car's really been sucking ***** on the low end. once I hit about 3000 rpm, you can hear the tone of the engine change and the thing just PULLS. and it's not VTC of the power valve. something else, and it's been getting worse as the weather warms up. sounds like a knock sensor/octane problem to me.
06-02-2002, 06:44 AM
#12
Senior Member
Join Date: Aug 2000
Posts: 615
I too will be replacing my knock sensor in the next couple weeks for my low end is getting more and more unacceptable. It got better when I increased my timing after replacing my VTC's and all, but it's about back to where it was, which leads me to believe the knock sensor is corroded/bad. Good info on reusing the old intake gaskets, I bought news ones when I took the head off (I think they were $50 for the two from Courtesy) so mine should still be decent.
06-02-2002, 07:55 AM
#13
Senior Member
Join Date: Jan 2001
Posts: 2,105
KS+headwork questions
if i were to get far enough to clean the connectors on the knock sensor, how hard would it be to replace it? i'm thinking if i test it and its bad to just replace it then..of course, this'll be all around the time i'm getting new VTC and having my heads rebuilt..now just for an FSM.
also, if i were to replace the valve springs with those from a 300zx (new, not used), would i see a benefit? i mean, when i get an ECU, would i be able to rev higher, safely?
also, if i were to replace the valve springs with those from a 300zx (new, not used), would i see a benefit? i mean, when i get an ECU, would i be able to rev higher, safely?
06-04-2002, 11:10 AM
#15
Senior Member
Join Date: Jan 2001
Posts: 2,105
Re: The 300zx Valve springs fit?
Originally posted by JonnyMax
If so then I need to add that to my list.... TT or NA springs?
If so then I need to add that to my list.... TT or NA springs?
06-05-2002, 07:50 AM
#16
you should be able to find the information on the valve springs from your local dealer if they're willing to spend a few minutes of research on the computer.
also, why would you want to change valve springs? the VE and VG30DE both have about the same red line and rev limiter..
and please start another thread if you wish to continue discussing this. this thread was originally about the knock sensor, not valve springs.
also, why would you want to change valve springs? the VE and VG30DE both have about the same red line and rev limiter..
and please start another thread if you wish to continue discussing this. this thread was originally about the knock sensor, not valve springs.
10-11-2004, 02:57 PM
#18
Originally Posted by fdaza
I am having hard time starting my 89 maxima in the mornings. Seems like there in no current going to the spark plugs, could this be a problem with the knock sensor????
Holy old post, Batman. The knock sensor sluggishness is primarily a VE problem. And the symptoms you describe don't have anything to do with the knock sensor.
03-21-2007, 01:41 PM
#19
Newbie - Just Registered
Join Date: Mar 2007
Posts: 9
I just pulled my codes from the computer and I got a 34. According to my repair manual it is a knock sensor. I have already ordered a new one from EBAY.(saved 100$ off dealer price.)
My question is, Could a knock sensor cause the engine to backfire and knock, When It warms up my Maxima drives bad, very low on power and surges/backfires. or is that somthing else. I pulled my spark plugs and the 3 that came out of the rear bank had white insulators while the three out of the front bank had the standard off white/tan color. According to what I have read this could mean lean fule condition or spark knock.
So then I might need to replace the rear bank of injectors. ?? and the knock sensor.
Has anyone else experienced this type of problem from just a bad knock sensor.
I have already replaced the gas filter and checked the air filter. I also did a compression test. I got 175PSI in all cylinders +/- 2 PSI with a cold engine.
any help appreciated.
thanks guys.
93 SE
My question is, Could a knock sensor cause the engine to backfire and knock, When It warms up my Maxima drives bad, very low on power and surges/backfires. or is that somthing else. I pulled my spark plugs and the 3 that came out of the rear bank had white insulators while the three out of the front bank had the standard off white/tan color. According to what I have read this could mean lean fule condition or spark knock.
So then I might need to replace the rear bank of injectors. ?? and the knock sensor.
Has anyone else experienced this type of problem from just a bad knock sensor.
I have already replaced the gas filter and checked the air filter. I also did a compression test. I got 175PSI in all cylinders +/- 2 PSI with a cold engine.
any help appreciated.
thanks guys.
93 SE
03-21-2007, 01:59 PM
#20
Originally Posted by concordmike
I just pulled my codes from the computer and I got a 34. According to my repair manual it is a knock sensor. I have already ordered a new one from EBAY.(saved 100$ off dealer price.)
My question is, Could a knock sensor cause the engine to backfire and knock, When It warms up my Maxima drives bad, very low on power and surges/backfires. or is that somthing else. I pulled my spark plugs and the 3 that came out of the rear bank had white insulators while the three out of the front bank had the standard off white/tan color. According to what I have read this could mean lean fule condition or spark knock.
So then I might need to replace the rear bank of injectors. ?? and the knock sensor.
Has anyone else experienced this type of problem from just a bad knock sensor.
I have already replaced the gas filter and checked the air filter. I also did a compression test. I got 175PSI in all cylinders +/- 2 PSI with a cold engine.
any help appreciated.
thanks guys.
93 SE
My question is, Could a knock sensor cause the engine to backfire and knock, When It warms up my Maxima drives bad, very low on power and surges/backfires. or is that somthing else. I pulled my spark plugs and the 3 that came out of the rear bank had white insulators while the three out of the front bank had the standard off white/tan color. According to what I have read this could mean lean fule condition or spark knock.
So then I might need to replace the rear bank of injectors. ?? and the knock sensor.
Has anyone else experienced this type of problem from just a bad knock sensor.
I have already replaced the gas filter and checked the air filter. I also did a compression test. I got 175PSI in all cylinders +/- 2 PSI with a cold engine.
any help appreciated.
thanks guys.
93 SE
definitely check the injectors and the harness...but don't be so quick to yank out the knock sensor just yet.
03-21-2007, 02:16 PM
#21
But also keep in mind that if it's backfiring, that means there's fuel inside your exhaust that's burning after the fact. which means you're running rich possibly.
check ignition timing as well as the knock sensor.
what fuel are you running?
cleaned injectors lately?
check ignition timing as well as the knock sensor.
what fuel are you running?
cleaned injectors lately?
03-21-2007, 02:17 PM
#22
Originally Posted by concordmike
I just pulled my codes from the computer and I got a 34. According to my repair manual it is a knock sensor. I have already ordered a new one from EBAY.(saved 100$ off dealer price.)
My question is, Could a knock sensor cause the engine to backfire and knock, When It warms up my Maxima drives bad, very low on power and surges/backfires. or is that somthing else. I pulled my spark plugs and the 3 that came out of the rear bank had white insulators while the three out of the front bank had the standard off white/tan color. According to what I have read this could mean lean fule condition or spark knock.
So then I might need to replace the rear bank of injectors. ?? and the knock sensor.
Has anyone else experienced this type of problem from just a bad knock sensor.
93 SE
My question is, Could a knock sensor cause the engine to backfire and knock, When It warms up my Maxima drives bad, very low on power and surges/backfires. or is that somthing else. I pulled my spark plugs and the 3 that came out of the rear bank had white insulators while the three out of the front bank had the standard off white/tan color. According to what I have read this could mean lean fule condition or spark knock.
So then I might need to replace the rear bank of injectors. ?? and the knock sensor.
Has anyone else experienced this type of problem from just a bad knock sensor.
93 SE
A bad knock sensor usually will not cause backfiring,when the knock sensor fails,the ecu will automaticly retards timing to the extreme until you replace the sensor,you could bypass the ecu failsafe with 470k ohm resistor in the harness plug going to the sensor,but you Absolutely must run PREMIUM FUEL until the sensor is replaced..It is very difficult to get to the sensor[labor wise],it is under the intake plenum/injector rail/coolant pipe,in the valley between the cylinder heads..
The backfiring/stumbling issue may be a bad coolant temp sensor and/or one of the coils may be failing..
Also,a stuck open fuel injector could cause a backfiring issue...
03-21-2007, 06:27 PM
#24
Newbie - Just Registered
Join Date: Mar 2007
Posts: 9
I read in another thread that the injectors used on my motor do not respond well to cleaner/ additives ect. I dont know if this is true. Somthing about a non pintle design.
I will pick up a coolant temp sensor tonight and screw it in there. Does anyone know how many ohms of resistance the injectors are supposed to have. I have a DMM I can test them with.
I will pick up a coolant temp sensor tonight and screw it in there. Does anyone know how many ohms of resistance the injectors are supposed to have. I have a DMM I can test them with.
03-21-2007, 06:33 PM
#25
Originally Posted by concordmike
I read in another thread that the injectors used on my motor do not respond well to cleaner/ additives ect. I dont know if this is true. Somthing about a non pintle design.
I will pick up a coolant temp sensor tonight and screw it in there. Does anyone know how many ohms of resistance the injectors are supposed to have. I have a DMM I can test them with.
I will pick up a coolant temp sensor tonight and screw it in there. Does anyone know how many ohms of resistance the injectors are supposed to have. I have a DMM I can test them with.
The injectors should ohm out between 11-14 ohms...
Thread
Thread Starter
Forum
Replies
Last Post
kjlouis
4th Generation Maxima (1995-1999)
11
11-24-2018 06:09 AM
jerrod99_se-l
4th Generation Classifieds (1995-1999)
2
08-27-2015 08:27 PM
maxinout93
5th Generation Maxima (2000-2003)
3
08-20-2015 02:17 AM